Methods and apparatus for deploying sheet-like materials

Abstract

Implant delivery systems for delivering sheet-like implants include a delivery shaft, an implant expander, a sheath, and a sheet-like implant. In some embodiments, the delivery shaft has a proximal end and a distal end. The implant expander is mounted to the distal end of the delivery shaft. The implant expander includes a central portion and a plurality of leg portions radiating from the central portion. The implant expander is evertable between an unstressed configuration in which a distal surface of the implant expander defines a concave surface, and a first compact configuration in which the distal surface of the implant expander defines a convex surface. The implant expander has a first lateral extent when the implant expander is free to assume the unstressed configuration. The sheath defines a lumen having a lumen diameter. At least a portion of the delivery shaft is slidably disposed in the lumen. The lumen diameter is smaller than the first lateral extent of the implant expander so that the sheath holds the implant expander in the first compact configuration when slidably disposed therein. The sheet-like implant overlays at least a portion of the distal surface of the implant expander with portions of the sheet-like implant extending between the leg portions of the implant expander and the sheath. Methods of treating a rotator cuff of a shoulder are also disclosed.

What is claimed is: 
     
         1 . An implant delivery system adapted to deliver a sheet-like implant to a target tissue, the implant delivery system comprising:
 the sheet-like implant having an upper surface and a lower surface, the lower surface configured to be positioned against the target tissue;   a delivery shaft having a proximal end and a distal end;   an implant expander positioned proximate the distal end of the delivery shaft, the implant expander configured to engage the upper surface of the sheet-like implant to move the sheet-like implant between a compact configuration and an expanded configuration; and   a projection extending distally from the delivery shaft along a longitudinal axis of the delivery shaft, the projection extending through the sheet-like implant in both the compact configuration and the expanded configuration.   
     
     
         2 . The implant delivery system of  claim 1 , wherein the projection comprises a pointed distal tip pointing in a distal direction along the longitudinal axis. 
     
     
         3 . The implant delivery system of  claim 2 , wherein the pointed distal tip is configured to penetrate into the target tissue. 
     
     
         4 . The implant delivery system of  claim 1 , wherein the implant expander is movable relative to the delivery shaft to move the sheet-like implant from the compact configuration to the expanded configuration. 
     
     
         5 . The implant delivery system of  claim 4 , wherein the implant expander includes a first leg and a second leg. 
     
     
         6 . An implant delivery system adapted to deliver a sheet-like implant to a target tissue, the implant delivery system comprising:
 a delivery sheath having a lumen therein;   the sheet-like implant having an upper surface and a lower surface, the lower surface configured to be positioned against the target tissue;   a delivery shaft having a proximal end and a distal end and movably disposed in the lumen of the delivery sheath;   an implant expander positioned proximate the distal end of the delivery shaft, the implant expander configured to engage the upper surface of the sheet-like implant to move the sheet-like implant between a compact configuration when constrained within the delivery sheath and an expanded configuration when deployed from the delivery sheath; and   a projection extending distally from the delivery shaft along a longitudinal axis of the delivery shaft, the projection extending through the sheet-like implant in both the compact configuration and the expanded configuration.   
     
     
         7 . The implant delivery system of  claim 6 , wherein the projection comprises a pointed distal tip pointing in a distal direction along the longitudinal axis. 
     
     
         8 . The implant delivery system of  claim 7 , wherein the pointed distal tip is configured to penetrate into the target tissue. 
     
     
         9 . The implant delivery system of  claim 7 , wherein the pointed distal tip penetrates through the sheet-like implant in the expanded configuration. 
     
     
         10 . The implant delivery system of  claim 6 , wherein the implant expander is movable relative to the delivery shaft to move the sheet-like implant from the compact configuration to the expanded configuration. 
     
     
         11 . The implant delivery system of  claim 10 , wherein the implant expander includes a first leg and a second leg. 
     
     
         12 . A method of deploying a sheet-like implant comprising:
 positioning an implant delivery device proximate a target tissue site, the implant delivery device comprising:
 a delivery shaft having a proximal end and a distal end; 
 an implant expander positioned proximate the distal end of the delivery shaft; 
 a projection extending distally from the delivery shaft along a longitudinal axis of the delivery shaft; 
 a sheath having a proximal end and a distal end and defining a lumen, wherein at least a portion of the delivery shaft is slidably disposed in the lumen; and 
 the sheet-like implant disposed at least partially within the sheath in a compact configuration with the projection extending through the sheet-like implant from an upper surface of the sheet-like implant to a lower surface of the sheet-like implant; 
   advancing the delivery shaft distally through the sheath to cause the implant expander and the sheet-like implant to advance through a distal opening of the sheath, wherein after advancing through the distal opening of the sheath, pressing the implant expander against the upper surface of the sheet-like implant in order to position the lower surface of the sheet-like implant against the target tissue site in an expanded configuration; and   withdrawing the delivery shaft and the implant expander proximally from the sheet-like implant.   
     
     
         13 . The method of  claim 12 , further comprising moving the implant expander relative to the delivery shaft to move the sheet-like implant from the compact configuration to the expanded configuration. 
     
     
         14 . The method of  claim 13 , further comprising penetrating the projection into the target tissue site. 
     
     
         15 . The method of  claim 14 , wherein the projection includes a pointed distal tip. 
     
     
         16 . The method of  claim 12 , wherein the implant expander includes a first leg and a second leg.